Method of making bags



Nov. 24, 1953 JQF, DOYLE 2,660,100

' METHOD oF MAKING BAGS Filed Dec. 11, 1948 INVENTOR /Me-s Dame- BY i E: ATTORNEY Patented Nov. 24 1953 TED S TTES PTENT OF F ICE.

METHOD 0F MAKING BAGS James' F( Doylev Forest Hills,` N. Y., assig'nor to ArkellI Safety Bag Company, New York, N. Y., a corporation of New York Application December 11, 1948, Serial o. 64,768

(Cl. k93l-35) Y l zhlegpresent. invention relates to a method of irmingbagsyand has special reference t'osleeve valvestliatare.particularly adapted for multi-ply crin'leied paper. bags of. .the type of the one described-.and claimed. in the patent to Edward l). Greene, No. 72,31.,87`6dated March 30, 1943. nero'f theobjeetsof the` invention is to providel a method. of forming` abag of the character indicated having a sleeve valve which is of simple and stronglconstruction and convenient in use, and maybe easily .formed either by hand or by machine..r l Y a Another..object of' theinvention is to provide anovel and. improved rhethod of forming a sleeve valve `for a 'bagoflths character.

, 'S'tillanother object of the invention is to provide anovel and improved method of closing the end; of: aloag` ofthe character indicated.

` 'The invention isiIIustrated by Way of example intheaccompanying drawings, in which:

A -igure -1 its aside view-of a bag-havinga portion thereof` broken. away to save space, .and with a sfheetappliedthereto from which thesleeve of tiravalve ofthe bagl is to be formed;

l Figwgisa transverse sectional View,A taken substantially on the-line RAZ of Fi-g; 1;

u1"ig-.3 i-sa sectional View,` partly in elevation, ofconecorner-of the bag with the corner tucked intofiorm a valve and With the sleeve attached theretofthe section being taken substantially on the linee-ies of. Fig.. 4;

igcfi is a sectional view,-taken substantially ontheline 4-- Yof `Fig. v3

Fig.35risa1sideview of the upperportion of a v bagwith its upper end closed by a sealing strip and a lineoffstitohes, -thesealing strip also being employed=-te-close-the outerend of the valve sleeve?, I Fig.` 6 hisfafLletai-l sectional view taken on the line6- 6ofliiig.-5; -igi iso. View corresponding to a portion of Fig. 5, butillustratingfanother means that 'may be employed for closing the outerfend of the valve Sleeve.

Fig.v 8 is a sectional view, taken on the line B-feofnF-g-.iit al1-rdf. i

Fig. 9 is `a view corresponding to Fig. `3, but with the valve"a"nd valve sleeve formed in a gusseted bag,1tlfi"evalve sleeve being ofl another Amodified i s 'The bag-iuust-ratedin 'the Adrawing is a multithereof -e'rltendedtransversely of the bag "topro- Vide sforwloh'gitudinafl 'stretchability The lower end of the'fbagisrshown closed by'a tape d folded over the lowerv'endsoifthesideiwalls of the bag, and a line of stitches 6. This bag is of the type l@f thfffone described and claimed in saidGr-eene 4itent'2,3'lth8'76 -t'o which 'reference may be had for a full and complete description of the same.

extending crinkles, flattened 'co1'-`ruga'tions,v orother means to increase the 4flexibility thereof and provide for stretch'ability in more thanv one? direction.

This sheet 8 isfolded over the upper end por`-V` tion of One of the longitudinal edges' of i'fhibag with its coating on its inner side. Heat and .pres

sure are then applied' to the portions of the' sides.: of the sheet that extend over the corner ofthe: bag that is to be tucked in to form tl vali/eso? as to heat-seal the sheet to said corrienthe boundary of this corner being dened by4` th'ef diagonal dotted line l 0 and thev heat-sealing area;Y being indicated at ll. Such heat and pressure sealing forces the ridges'and valleys o'f the erin kled sheet into a more or less nested relationshirt with the ridges and valleys of the crinkles .in the outer surface of the bag and adhesively secures them thereto, and thusra strong and tight bondi is provided throughout the secured areas of the sheet and corner of the bag.

After the sheet has thus Abeen securedin position, said corner of the bag is folded or tucked `in on the line l0 to -for'ni a valve having side Walls `I2 and a horizontal bottoml Wall portion I4.

The attached sheet 8 is folded infwith the corner ofthebag and assumes a horizontal positionas shown in FigS. The ends of the sheet extend beyond the ends of" the valve, the longi-A tudinal edges of the sheet are flush withth upper end edges of the bag, and the sides ofthe sheet are secured to the side walls 2 of the valve by the heat and pressuresealing-fabove described.

rIhe upper end of the bag -is preferablyclosed by a-Lstrip or tape t6 of `crink-led paper which. has' itsinner side coated with :a thermoplastic: resin as in the'i'iaseof'the coating on kone :side: of the sheet 8, the'crinkles'"extending longitudi-v nally of the tape. This-tape'is folded over the upperend edges ofthebag 'andov'er the' project ing longitudinal edges o'f'thesheet t," `rand is-'se- 'cured in position by a lline'of""stitoh`es" 181.' I-Ie'a't. and pressure are then-'appliedto the tapeiliv 'sos as to a'dhesively secure the 'strip over the sides'. ortnefbag and to causetre'plastic"refusewith` the plastic coating on `the veuve' sneetcr' sieevet.

the crinkles in the "tape VHVnest'in'g vv'i'thwtlie-v crinkles in the bag Walls and valve sleeve. By

:sides of the sleeve.

In applying the sleeve to a gusseted bag as;

shown in Fig. 9, the Valve 20 having the usual valve extension 22 is first formed in the corner of the bag and then the valve sheet 8 is folded fand inserted in the valve.

The sheet may then be secured in the valve by the application of heat and pressure applied to the side Walls of the bag -over the valve, so as to fuse the plastic coating lon the outer side of the sheet to the side Walls of the valve.

The thermoplastic coating on the valve sleeve also enables the outer end of the valve to be :securely sealed. One manner of thus sealing the .end of the valve sleeve is illustrated in Fig. 5 in Vwhich the end of the tape I8 is provided with :an extension 2e which is folded down over the :end of the sleeve and against the coated outer` Heat and pressure are then :applied to the sides of this extension 24 so as to cause its coating to tightly fuse with the coat- Ting on the sleeve. In Figs. 7 and 8 the end of the sleeve is shown sealed by turning in the ends 26 thereof and heat-sealing. In Fig. 9 the end 'of one of the Walls of the sleeve is provided with fa cutaway portion 28 whereby the adjacent portion of the other Wall of the sleeve may be folded over and heat-sealed to the other side of the sleeve.

It will be apparent that applicants sleeve valve is Vof simple and strong construction and convenient in use; may be easily formed either by hand or machine, and that it is particularly adapted for multi-ply crinkled paper bags such as that illustrated and described. Owing to the substantial nesting of the crinkles in the valve sleeve and side walls of the valve a secure seal is provided upon fusing of the coating by the application of heat and pressure, and there is no danger of sifting or other leakage occurring between the sleeve and the valve walls. The thermoplastic sealing of the crinkled closure strip or tape l ensures against leakage through the needleholes or beneath the tape.

While itis preferred to employ the thermoplastic coated valve sleeve and sealing tape which have the advantages above described, it will be apparent that in certain cases unccated material may be employed, the securing being accomplished by pasting or gluing. Also that the sleeve valve may be applied to other types of bags, of paper or other material.

What I claim is:

1. The method of forming a sleeve valve in a bag of the class described which comprises folding a sheet having a thermoplastic coating on the inner side thereof over the upper end portion of one of the longitudinal edges of the bag, applying heat and pressure to the portion of the sheet overlying the adjacent corner of the bag to cause the coating to adhesively secure said sheet over ,said edge and to the side Walls of said corner, tucking in said corner of the bag with said sheet attached to form a valve, the folded sheet being so positioned that the ends thereof when the corner is folded in extend beyond the inner and outer ends of the valve and the longitudinal edges of the sheet are substantially flush with the upper edges of the bag walls, folding a tape having a thermoplastic coating on its inner side over the upper edges of the bag and over the longitudinal edges of the sheet, and applying heat and pressure to said tape to cause it to adhere to the upper margins of the side Walls of the bag and the longitudinal margins of said sheet.

2. The method of forming a sleeve valve in a multi-ply crinkled paper bag of the class described having the crinkles extending transversely of the bag, Which comprises longitudinally folding a sheet of crinkled paper having a thermoplastic coating on the inner side thereof over the upper portion of one of the longitudinal edges of the bag, applying heat and pressure to the portions of the sheet overlying the adjacent corner of the bag to cause the coating to adhesively secure the sheet over said edge and to the side Walls of said corner of the bag, tucking in said corner of the bag with said sheet attached to form a valve, the folded sheet being so positioned that the ends thereof When the corner is folded in extend beyond the inner and outer ends of the valve and the longitudinal edges of the sheet are substantially ush with the upper edges of the bag Walls, and applying heat and pressure to the upper edges of the bag Walls to cause said coating to secure said upper edges and the longitudinal edges of the sheet together.

3. The method of forming a sleeve valve in a multi-ply crinkled paper bag of the class described having the crinkles extending transversely of the bag, which comprises longitudinally folding a sheet of crinkled paper having a thermoplastic coating on the inner side thereof over the upper portion of one of the longitudinal edges of the bag, applying heat and pressure to the portions of the sheet overlying the adjacent corner of the bag to cause the coating to adhesively secure the sheet over said edge and to the side Walls of said corner of the bag, tucking in said corner of the bag with said sheet attached to form a valve, the folded sheet being so positioned that the ends thereof When the corner is folded in extend beyond the inner and outer ends of the valve and the longitudinal edges of the sheet are substantially flush with the upper edges of the bag Walls, folding a strip of crinkled paper over the upper edges of the side Walls of the bag and over the longitudinal edges of said sheet, said strip having a thermoplastic coating on its inner side, securing said strip in position by a line of stitches extending therethrough and through the side walls and longitudinal margins of said sheet, and applying heat and pressure to the sides of the strip to cause the coating on the strip to adhesively secure it to said side Walls and to seal the needle holes, and to cause the coating on the sheet to adhesively secure the longitudinal Vedges of the sheet and the upper edges of said side walls together.

JAMES F. DOYLE.

References Cited in the file of this patent UNITED STATES PATENTS Number Great Britain Sept. 8, 1947 

